What are the treatment options for primary hyperhidrosis?

Treatment of Primary Hyperhidrosis

Start with topical aluminum chloride 10-20% solution applied nightly to affected areas as first-line therapy for axillary, palmar, and plantar hyperhidrosis, with the exception of craniofacial sweating where topical glycopyrrolate is preferred. 1, 2

Initial Assessment

Before initiating treatment, evaluate for secondary causes by:

• Checking thyroid function tests to exclude hyperthyroidism 1
• Reviewing all medications that may cause excessive sweating 1
• Assessing iron stores, vitamin D, and zinc levels 1

Treatment Algorithm by Anatomic Location

Axillary Hyperhidrosis

First-Line: Topical Aluminum Chloride

• Apply 10-20% aluminum chloride solution nightly to dry skin 1, 2
• Aluminum sesquichlorohydrate 20% foam is an alternative that reduces sweating by 61% with minimal irritation 3
• Common side effect is skin irritation; if this occurs, reduce application frequency 4, 3

Second-Line: Botulinum Toxin A (OnabotulinumtoxinA)

• FDA-approved for axillary hyperhidrosis unresponsive to topical therapy 2, 5
• At 4 weeks, 92% of patients achieve ≥2-grade improvement on the Hyperhidrosis Disease Severity Scale (HDSS) compared to 33% with aluminum chloride 5
• Provides 3-6 months of relief; requires repeated injections 1
• May cause temporary weakness in adjacent muscles 1

Third-Line: Microwave Therapy or Surgery

• Local microwave therapy is a newer option for refractory axillary hyperhidrosis 2
• Surgical excision of axillary sweat glands for severe cases, though this may cause unsightly scarring 4, 2

Palmar and Plantar Hyperhidrosis

First-Line: Topical Aluminum Chloride

• Apply 10-20% aluminum chloride solution nightly 2, 6
• Aluminum sesquichlorohydrate 20% foam reduces palmar sweating effectively with minimal irritation 3

Second-Line: Iontophoresis

• Simple, well-tolerated method without long-term adverse effects 4, 2
• Requires long-term maintenance treatments to keep patients symptom-free 4
• Should be considered when topical therapy fails 2

Third-Line: Botulinum Toxin A

• Considered first- or second-line for palmar hyperhidrosis 2
• Requires repeat injections every 6-8 months 4

Fourth-Line: Endoscopic Thoracic Sympathectomy

• Reserved for severe cases unresponsive to all other therapies 2, 6
• Complications include compensatory hyperhidrosis (sweating in other areas), gustatory hyperhidrosis, Horner syndrome, and neuralgia—some patients find these worse than the original condition 4

Craniofacial Hyperhidrosis

First-Line: Topical Glycopyrrolate

• Preferred over aluminum chloride for craniofacial sweating 2
• Aluminum chloride may cause scalp irritation or scaling if used on the head 1

Second-Line: Botulinum Toxin A

• Considered first- or second-line for craniofacial hyperhidrosis 2

Systemic Therapy for Severe or Generalized Cases

Oral Anticholinergics

• Useful adjuncts when other treatments fail 2
• Glycopyrrolate oral solution is FDA-approved for pathologic drooling in children, dosed at 0.02-0.1 mg/kg three times daily (maximum 3 mg per dose) 7
• Must be given 1 hour before or 2 hours after meals to optimize absorption 7
• Common adverse effects include dry mouth (40%), constipation (35%), vomiting (40%), flushing (30%), nasal congestion (30%), and urinary retention (15%) 7
• The dose required to control sweating often causes significant adverse effects, limiting effectiveness 4
• Contraindicated in glaucoma, paralytic ileus, unstable cardiovascular status, severe ulcerative colitis, and myasthenia gravis 7

Grading Severity and Treatment Response

Use the Hyperhidrosis Disease Severity Scale (HDSS) to guide treatment decisions 2, 5:

1. Sweating is never noticeable and never interferes with daily activities
2. Sweating is tolerable but sometimes interferes with daily activities
3. Sweating is barely tolerable and frequently interferes with daily activities
4. Sweating is intolerable and always interferes with daily activities

• HDSS score 1-2: Start with topical aluminum chloride 2
• HDSS score 3-4: Consider botulinum toxin A or iontophoresis earlier in the treatment algorithm 2, 5

Critical Pitfalls to Avoid

• Do not use incision and drainage for hyperhidrosis lesions due to nearly 100% recurrence rate 1
• Do not perform simple excision without considering deroofing techniques for chronic lesions 1
• Warn patients about compensatory hyperhidrosis before endoscopic thoracic sympathectomy, as this complication can be more distressing than the original condition 4
• Avoid high ambient temperatures when using anticholinergic medications, as they reduce sweating and can cause heat prostration, fever, and heat stroke 7
• Do not drive or operate machinery while taking oral anticholinergics due to drowsiness and blurred vision 7

When to Escalate Treatment

• If topical aluminum chloride fails after 4 weeks of nightly application, escalate to botulinum toxin A or iontophoresis 2, 5
• If botulinum toxin A or iontophoresis fails, consider oral anticholinergics 2
• If all medical therapies fail and hyperhidrosis is severe (HDSS 4), refer for surgical consultation 2, 6